Microphone.



G. A. NUSSBAUM. IooPHoNE.

APPLIOATIOII FILED IAN.26, 1911,

1,012,217. Patented nec. 19, 1911.

GUILLAUME ARNAUD NUSSBAUM, OF LONDON, ENGLAND.

MICROPHONE.

.specification ot Letters Patent.

Patented Dec. 19, 1911.

A.application led January 28, 1911. Serial No. 605,303.

T o all whom 'it may concern:

Be it known that I, GUILLAUME ARNAUD NUSSBAUM, a, subject of the Fling of Great Britain, residing at London. England, have invented Improvements in ltlicroiiihoncs, of which the following is a specillcation.

This invention relates to microphones for telephonie use and it has for its general object to provide a micropl'nme of simplified construction, very suitable for long distance and common battery circuits. which shall be )nore reliable than those heretofore proposed and 'in which packing of the carbon granules is eli'ectually prevented.

One important object ot the invention is to build up the microphone ol" 4disks separated and assembled to forni a granule cell so constituted that the vibrations of the entire cell and the air set in motion between the disks prevent packing of the granules.

Another object of the invention is to provide a micro hone, that may be mounted solid back ashion or in such a manner that sound wares act on both sides thereof simultaneously, wherein the vibrations of sound waves are communicated lo intermediary disks and the carbon gratuites. such combined vibrations Causing great variations in the resistance of the microphone circuit.

lV ith these and other objects, the invention consists in the various combinations of elements hereinafterl described and claimed.

In the accompanying drawings Figure 1 is a transverse section of one 'form of the improved lnicrt'lphonc. Fig. 2 is a :'aectional plan of the same. Figs. and 4 are views .similar lo Figs. l and of another form of 'the l'nicroplmne. Figs. .fi to 8 are transverse sections of further nnnlifirations.

As shown in Figs. l and 2 the microphone comprises a series of thin resilient plates or diaphragme the two outer ones o of which, preferably carbon, are plain disks. while the intermedmry oni-s b are each formed with a central hole. The intermediary plates b may be of carbon, or ot' nie-tal, paper, cardboard, mica, liber and (he like. The several intermediarir plates b must be separated from each other in .such a manner that a. ver)l thin air "a p remains between adjacent, plates so thin In fact that carbon ranules w cannot enter between them. this eilig convenienth.I eilected by interposing thm periliheral washers. c of paper, mica, liber or the like. For the sake of clcarncssrthesc air gaps are purposely exaggerated in the drawm .[he microphone shown in Fi 3 nnd4 is similar to that of Figs. l an 2 with the addition however of concentric washers ri between the outer diaphragms a and intermediary plates b. These washers cl may be of insulating material or, when it is desired to reduce the resistance of the microphone, of carbon.

In Fig. 5 the outer diaphraghsaare shown separated from the plates b by peripheral washers o and concentric carbon disks c, while in Fig. 6 one diaphragm ais separated from one plate b at the center, by a washer d and the other diaphragm c from its adjacent plate b by a disk e. For the purpose of still further reducing the resistance of the apparatus the peripheral washers c* may be of conducting material.

ln Fig. 7 one diaphragm a, z'. e. the rear one, is atlixed directly to the adjacent perforated plate b.

l'n Fig. 8 the intermediary plates b are of smaller diameter than the diaphragme a which in this example are adapted to be clamped to opposite facesof an outer ring f of liber or other material insulated or of an insulating character. g is a metal diaphragm against which one of the diaphragme a, can be clamped.

What l claim is:--

1. A microphone comprising a series of perforated and imperforate plates of conducting material arranged coaxially with the imperorate plates' outermost and mate- -rial separating the several plates axially one with respect to another and maintainingr air spart-.s between them. such plates forni.- ng collectively a vibrating granuleeontaining coll, substantially as described.

2. A microphone comprising a series of perforated and im ierforate lates of resilient material hold in space( relationship one with respect to another with air spaces lwtwcen them. the said plates forming collet-:lively a vibrating granule containing cell the lateral wall of which is formed by the inner periphery of a erforated plate, and granules located in said cell and 1n contact with said rwrorated plate.

3. microphone comprising e series of perforated and imperforate lates of resilient material held-in spaced) relationship one with respect to another with air spaces between them, the said plates forming co1- lectively a vibrating ranule containing cell the lateral wall of w ich is formed by the inner peripheries of a liirality of perforated plates, and granu es located in said cell and in contact with said perforated plates.

4. A microphone comprising a series of,

perforated an imperforate plates, and separating material arranged between said plates nearthe outer neripheries thereof to form air spaces between the plates.

5. A microphone comprising a series of perforated and iniperforate plates of resilient material arranged adjacent to one another with air spaces between them and vibration transmitting means between the central portion of an outer imperforate plate and the adjacent perforated plate.

6. A microphone comprising a series of perforated and iinperforate plates of resilient material arranged adjacent to one another witli air spaces between them and vibration transmittin means between the central portion of eac outer plate and the adjacent imperforate plate.

7. A microphone comprising a series of perforated and imperforate plates of resilient material arranged adj aeent to one another witli air spaces between them and a vibration transmitti ring arranged between the central portion of an outer imperforate plate and the inner edge portion of the adjacent perforated plate.

8. A microphone comprising a series of perforated and imperforate plates of re-z silient material arranged adjacent to one another with air spaces .between them and a vibration transmitting ring arranged between each of the outer imperforate and the inner edge portion of the adjacentperforated plate. 1

9. A microphone comprising a series of perforated plates of resilient material,a pair of iinperfoi'ate diaphragme between' which the perforated plates are disposed, and insulating peripheral washers separating the perforated plates one from another.

10. A microphone comprising a series of perforated plates of resilient materiaLa., pair of iiiiperforate diaphragme between `which the perforated plates are disposed, and peripheral s :icing washers separating the per forated liites one from another and from the diap raginf..

1l. -A microphone comprising a series of perforated plates of resilient material, a pair of imperforate diaphragmsbetween which the perforated plates are disposed, peripheral spacing washers separating the perfo rated, plates, peripheral spacing washers separating the outermost of the perforated plates from the diaphragins, and spacing plates washers perforated to correspond with the perforations in the plates dis osed between the outermost lates and the iaphragms in register with t e perforations in the plates.

12. A microphone comprising a. series of perforated plates of resilient material held in spacedrelationship one with res ect-to anot er, 'a pair of conducting diap ms between which the rforated plates are isposed and spacing evices o'f conducting ma.- terial adapted to secure plate and dia.-` phragm separation.

13. A microphone comprising a series of perforated plates of resilientmaterial held 1n s aced relationship one with Tes ect to anot er, a pair of conducting diapiiragms of larger area between which the perforated plates are disposed and a ring surrounding the plates and separating the diaphragm.

14. A microphone comprising a series of perforated plates of resilient material, a. pair of imperforate diaphragme of larger area between which the perforated plates are dis-4 posed, insulating peripheral wasliers separating the perforated plates one from another and a ring surroundi the. plates holdin the diaphragm in definite spaced relations iip one with respect to the other.

15. A microphone comprising a series of perforated plates of resilient material, a pair of imperforate diaphragme of larger area. between which the perforated plates are ing the diaphra m in de nite spaced rela- 1w tionship one wit respect to the other, spacing devices, disposed in register with `the perfor-ations in 'the plates, .seplarating the outermost plates from the diap ragins and a plate in complete surface contact-with the outermost diaphragm.

Signed at London England this 20th day.

4ot January 1911. y

GUILLAUME ARNAUD NUSSBUM.

Witnesses Airrnuii F. Bmionss,

J. J. BaouoHAM.

disposed, insulating peripheral washers sep- 

